Apple's Sept. 9 music event: What's Steve Jobs got up his sleeve?

New iPods? Check. With cameras? Very likely. iTunes 9? Why not. Steve Jobs on stage? Who knows. The Beatles on iTunes? Don’t count on it — but don’t count it out, either.

Apple’s (AAPL) invitation-only special event Wednesday could go either way.

It could be a ploy to get the press to publicize some relatively inconsequential improvements in Apple’s increasingly long-in-the-tooth iPod line (a product line that once accounted for anywhere from a third to half the company’s quarterly revenue and now brings in less than one fifth.)

Or it could signal the confluence of three classic Apple story threads:

A new and surprising confection of hardware and software that restores our sense of childlike wonder;

The reappearance of Apple’s iconic CEO, restored to health by the organ transplant that saved his life;

The digital debut — via iTunes — of one of the most influential bands in the history of popular music (and a Steve Jobs favorite), nearly 40 years after their break-up.

The timing is propitious.

The Beatles’ Apple Corps has not only settled its lingering legal disputes with Apple Inc., it has scheduled for the same day (9-9-09) the long-awaited release of the digitally remastered Beatles catalog and the much-anticipated video game Rock Band: The Beatles.

Meanwhile, Steve Jobs is back at work on the Cupertino campus — leaving his car parked, once again, in a handicapped space. To be sure, he’s been stepping back from the spotlight — even before his medical leave — giving other members of Apple’s management team a chance to shine. But if he’s ever going to appear in public again, this would seem a perfect opportunity.

Finally, it’s probably time to do something with the part of the iPod line that isn’t morphing into an iPhone. Either trim it — as Silicon Alley‘s Dan Frommer suggests — or take it in a new direction. Some megapixel eyes to go with those white ear buds would be a good start, last-minute reports of a technical hiccup notwithstanding.

Has Apple piqued your interest yet? Tune in Wednesday at 10 a.m. Pacific (1 p.m. Eastern). When we know something, you will too.